Method for the production of anhydrous hydrosulfites.



TIN

EMIL VON PORTHEIm. 0F PRAGUE,.AJISTRDA-EUNGAEY.

METHOD FOR THE PRODUGTIQN 0F ANHY'DRQUS HYDROSULFITES.

No Drawing.

Be it known that I, EMIL VON POR-PHEIM', a subject of the Emperor of Austria-Hum. gary. re iding at Prague, in Bohemia, Austria-Hungary, have invented certain new and useful Improvements in Methods for the Production oi. Anhydrous Hydrosullites; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertain-s to make and use the same.

It is well known that by heating an aqueous solution of bisulfites and formic acid, solutions are obtained of hi ghreducing qualities, lll which solutions the presence of hy dro-sulfites has been supposed, without, however, having been proved. Now 1 have found that hydro-sulfites are obtained if in the above-mentioned reaction the presence of water as a dissolving agent is excluded. By proceeding in this manner anhydrous hydrosulfites are obtained.

The proceeding may be as follows: Sulfitcs or bi-sulfites are allowed to enter into reaction with formic acid, or formiates with sulfurous acid, or formiates with sulfites 0r bisnlfitcs. or. lastly, sulfurous acid with formic acid in the presence of sulfites or formiates or other salts. I

Example 1': A mixture of 104 parts by weight oi drv sodium-bisulfite with 31.5 parts by weight of formiate of ammonium in alcohol of 96% is stirred and heated to boiling point. for one hour, and during this time sult'urous acid is carefully introduced, After decanting, washing with alcohol and drying. an cwccllcnt yield oi livdrosulfitc of high concentration is obtained. Of coursev this latter is free from metals and their oxids.

When the suspension of sodium bi sultile is boiled in alcohol. SO will he libcratcd and the resulting product will be the neutral sodium sulfitc l\ a.,SO. which does not cntcr the reaction with the tormiatc.

Tn or'rlcr to retard this decomposit on T introduce 0 into the solution. which does not. howcvcr. participate in the reaction. and is tlwrc't'orc omitted from the above couations.

Example 9: A. mixture of 58.5 parts by weight of sndiumch'lorid with a solution of Specification of Letters Patent Application. filed November 21, 1910, Serial no.

17' parts by weight of ammonia in alcohol of 90%, 64- parts by weight of sulfurous acid and 3115- parts by weight of formiate of ammonium is intensively boiled for 1-2' hours. The hydrosulfite is ellutriated from the unchanged sodium chlorid, is then decanted, washed with alcohol and freed from the alcohoh by being heated in cacao or in :1 current ofdby air. I

Example 3': An alcoholic solution of 17 parts by weight of ammonia is poured into an alcoholic solution of 64 parts by weight oi diox-id' of sulfur. To this -mixture is added. 68 parts by weight of formiate of potassium and the mixtiuneis well. stirned :gnd heated to boiling point for several ours.

Example 4: 63 parts by weight of formiate of ammonium are heated to melting point, and in the molten mass 104 parts by weight of a finely powdered dry bisulfite of sodium are introduced. After a short time the hydrosulfite thus obtained is cooled down and is freed from salts of sum I monium by subsequently being heated in cacao. The product contains at least 80% of sodium hydrosulfite. having the known properties of this salt, is pure white incolor and readily soluble in water. As impurities there are admixtures of reaction products and reagents consisting of thiosulfate of sodium. sulfate of sodium, sodium pyrosulfile and sodium chlorid.

The anhydrous hydro-sulfite results there-' Fore from the reaction of a substance con-' taining a formic acid radical (formic acid itself. or a formiate) with a substance containing sulturous acid (sulfurous acid itself or a salt containing it) with or without the presence of other salts, water being excluded as a dissolving agent or menstruum, and in lieu thereof l preferably use alcohol.

l claim-- J if The method of producing hydrosulfiles. which comprises reacting on a substance containing sulfurous acid with a substance containing a formic acid radical, said reaction taking place in the absence of water.

2. The method of producing hYdtO-Slll Patented. Aug. 27,1912.

fificsiflwhich comprises reacting on a sub 'stzi-ncc containing sulfur-oils nciri with for mic acid radical in an alcoholic monsiirnum.

3. The niozhod of producing hydrosnifites, which comprises reacting on a substance containing i snlfito with a subsi'anco containing a, formic acid-m icsl in the presence of sulfnrous acid and in a nienstrunni of alcohol.

4. The method of producing hydrosulfites which comprises reacting on 3 salt ccpabic of forming a sulfite, with sidfurous acid, and osubstancc containing a formic acid radical in an alcoholic mensirmnzn 5. The method -01? p pdncing hydrosuifites, which comprises fies-toting on a substance containing suifurous acid with 21 substance containing a formic acid radio-1] in a hot alcoholic menstruuin.

6. The method of producing hydrosuiflies, which comprises reacting on a snlfitc with a substance containing a formic acid radical in the presence of suifurous acid and 111 a bOlilllg mensirumn of alcohol.

7, The method, which comprises reacting ing with solfurousmcid upon a salt of an alkaline substance capable of forming a sul its and with a substance containing formic acid radical and in a hot sicoholionnensilrnnnz.

In testimony chat I claim the forogoing as my ini ention, I have signed my name in presence of two subscribing WiiIlBSSGS.

EMIL VON PORTHEIM.

Witnesses:

JEAN GBUND, CARL GRUIZD. 

